Polymeric compositions



United States Patent U.S. Cl. 260-2 12 Claims ABSTRACT OF THE DISCLOSUREThis invention relates to and covers new compositions of mattercomprising synthetic copolymeric materials prepared using as a comonomeran anhydride of an organo-amino-polyphosphonic acid having a generalformula as described hereinafter. An example of suchorgano-amino-phosphonic acid includes amino tri(methylene phosphonicacid).

The subject matter of the present invention was disclosed in ourco-pending application for Letters Patent, Ser. No. 538,193, filed inthe United States Patent Office on Mar. 29, 1966, now U.S. Patent No.3,395,113, granted July 30, 1968. The present application should beconsidered in conjunction with said application Ser. No. 538,193 andconsidered as a division of application Ser. No. 538,193.

This invention relates to organic polymeric compositions and, moreparticularly, provides novel polymeric compositions having increasedresistance to burning and a method for rendering polymeric compositionsflame retardant.

It is an object of this invention to provide new and useful polymericcompositions.

It is another object of this invention to provide methods for increasingthe resistance of organic polymeric compositions to the action of flamesand for making them more resistant to burning action in general.

An additional object of this invention is to provide in polymercompositions an organic phosphorus compound having reduced tendency todecompose and/or degrade from the polymer compositions when the polymersystem is subjected to elevated temperatures.

Other objects, advantages, and aspects of this invention will becomeapparent from a reading of the specification and the appended claims.

This invention provides, as new compositions of matter, an organicsynthetic polymer (linear or cross-linked) in combination with ananhydride of an organo-aminopolyphosphonic acid as defined herein.

Another aspect of this invention provides, as new compositions ofmatter, synthetic copolymeric materials prepared using as a comonomer ananhydride of an organo-amino-polyphosphonic acid as defined herein.

A still further aspect of this invention provides a method for reducingthe tendency of organic synthetic polymers to burn after a source ofburning heat has been removed from the polymeric composition byincorporating into the organic synthetic polymeric compositions ananhydride of an organo-amino-polyphosphonic acid as defined herein.

The anhydrides of organo-amino-polyphosphonic acids which are added to,blended with, or (JO-polymerized with the synthetic polymeric materialsto accomplish the above stated objects and aspects are disclosed anddescribed as well as methods for preparing the same in copendingapplication Ser. No. 538,198 of Riyad R. Irani and Robert S. Mitchellentitled Anhydrides of Organo- Phosphonic Acids, filed this same datewhich is incorporated herein by reference.

The organic phosphorus compounds which are useful in the presentinvention are anhydrides of organo-amino polyphosphonic acids having theformula:

wherein: n is an integer 0 to 1, X and Y are selected from the groupconsisting of hydrogen and alkyl groups containing from 1 to 6 carbonatoms and R is selected from the group consisting of hydrogen,aliphatic, aryl, alkaryl, aralkyl, alicyclic, and

(QM, l .l.

wherein m is an integer from 1 to 10, and R and R are each selected fromthe group consisting of hydrogen, alkyl groups containing from 1 to 6carbon atoms,

Y Ymi and R does not contain over 6 nitrogen atoms.

As used herein, the term anhydride(s) of organoamino-polyphosphonicacid(s) generically described all of the foregoing. Anhydrides oforgano-amino-polyphosphonic acids can be generally characterized bycontaining1 at least one anhydride (P-O-P) group per molecu e.

In the foregoing general formula, although X and Y are preferablyhydrogen, when X and Y represent alkyl groups, the groups may bebranched or straight chained and when R represents aliphatic groups, thegroups may be branched or straight chained as well as being saturated(alkyl) or unsaturated although it is preferred that if the groups areunsaturated they be ethylenically unsaturated and especially preferredare mono-ethylenically unsaturated (alkenyl) groups. Additionally, whenR represents groups containing alkyl moieties, i.e., aralkyl groups andthe like, such carbon chains may be of a straight chain structure orbranched chain structure and it is preferred that such contain from 1 toabout 20 carbon atoms. When R represents alicyclic groups such arepreferably 5 and 6 membered mono-cyclic alicyclic groups (cyclopentyland cyclohexyl). When R represents arylgroups or groups containing arylmoieties, i.e., alkaryl groups and the like, such groups are preferablymono-cyclic or dicyclic groups containing from 6 to 10 carbon atoms andespecially preferred is the mono-cyclic group containing 6 carbon atoms(phenyl). in addition, the foregoing mentioned hydrocarbyl groups maycontain substitucnt groups, such as, halides, (fluoride, chloride,bromide and iodide), alkoxy groups, sulfonyl groups, and the like.Although the hydrocarbyl groups can contain a plurality of suchsubstituent groups it is preferred that they contain only one suchsubstitutuent group per hydrocarbyl group. For most end use applicationsthe compounds of the instant invention should preferably contain notmore than about 25 carbon atoms associated with R, R R and X, and thereare few, if any, end uses in which these groups contain more than atotal of 50 carbon atoms.

In general, the anhydrides of the organo-amino-polyhosphonic acids canbe prepared by the process of reacting an organo-amino-polyphosphonicacid (as defined above) with an organic carboxylic anhydride, such asacetic anhydride, at temperatures above about 40 C. and preferably atreflux temperatures for a time sufficient to prepare the desiredanhydride product.

Particularly preferred anhydride compounds of the instant inventioninclude the amino tri(lower alkylidenephosphonic anhydrides), that is,anhydrides of amino tri(lower alkylidenephosphonic acids) having theform- O P=O Particularly preferred anhydride compounds of the instantinvention include the alkyl amino di(lower alkylidenephosphonicanhydrides), that is, anhydrides of alkyl amino di(loweralkylidenephosphonic acids) having the wherein: X and Y are selectedfrom the group consisting of hydrogen and alkyl groups containing from 1to 6 carbon atoms and R is an alkyl group containing from 1 to 20 carbonatoms.

Particularly preferred anhydride compounds of the instant inventioninclude the alkylene diamine tetra- (methylenephosphonic anhydrides),that is, anhydrides of alkylene diamine tetra(methylenephosphonic acids)having the formula:

HO OH wherein: n is an integer from 1 to 10 inclusive.

The anhydrides of organo-aminopolyphosphonic acids exhibit severalunique and/ or distinctive properties which include a distinct increase,usually greater than C. and in some cases greater than 50 to 100 C. ormore, in the melting point (which may in some instances be adecomposition point) for the anhydride of a particularorgano-amino-polyphosphonic acid over the correspondingorgano-amino-polyphosphonic acid aswell as a rate of reversion to thecorresponding organo-amino-polyphosphonic acid of greater than 1 gramper hour when grams of an anhydride of an organo-amino-polyphosphonicacid is slurried in 100 cc. of water for 1 hour at 40 C.

The anhydrides of organo-amino-polyphosphonie acids exhibit an infra-redabsorption spectra characteristic of a phosphonic anhydride (Nujol mull,Beckman model IR-4 spectrophotometer). Such spectra includes theanhydride linkage, P-O-P linkage, as an asymmetric vibration mode at anapproximate frequency of 900 to 980 cmf for anhydrides containing nogroups, a PO (free) stretching mode at an approximate frequency of 1250to 1350 cmf and for anhydrides containing groups, a P=O (hydrogenbonded) stretching mode at approximately 1150 to 1250 cm. which isstronger in intensity than a P-OH deformation mode at approximately 930to 1030 cm." as compared to the intensity of a P=O (hydrogen bonded)stretching mode and POH deformation mode of the parentorgano-amino-polyphosphonic acid. ['Reference: L. T. Bellamy, TheInfra-Red Spectra of Complex Molecules, John Wiley and Sons, Inc., NewYork, N.Y., Second Ed., 1959.]

Non-limiting examples of anhydride compounds suitable for use in thepresent invention include anhydrides of the followingorgano-amino-polyphosphonic acids:

amino tri(methylenephosphonic acid) dedecyl amino di(methylenephosphonicacid) pentamethylene diamine tetra(methylenephosphonic acid) aminotri(ethylidenephosphonic acid) methyl amino di(methylenephosphonic acid)decyl amino di(methylenephosphonic acid) tetradecyl aminodi(methylenephosphonic acid) methyl amino di(butylidenephosphonic acid)ethylene diamine tetra(methylenephosphonic acid) ethanol aminodi(methylenephosphonic acid) phenyl amino di(methylenephosphonic acid)cyclohexyl amino di(methylenephosphonic acid) cyclopentyl aminodi(methylenephosphonic acid) napthyl amino di(methylenephosphonic acid)hexylphenyl amino di(methylenephosphonic acid) dodecylphenyl aminodi(methylenephosphonic acid) phenylocetyl amino di(methylenephosphonicacid) phenyltetradecyl amino di(methylenephosphonic acid) phenylethylamino di(methylenephosphonic acid) oleyl amino di(methylenephosphonicacid) trimethylene diamine tetra(methylenephosphonic acid) hexamethylenediamine tetra(methylenephosphonic acid) decamethylene diaminetetra(methylenephosphonic acid) ethylene diamine tri(methylenephosphonicacid) ethylene triamine penta(methylenephosphonic acid) triethylenetetraamine hexa(methylenephosphonic acid) The presently providedanhydrides of organo-aminopolyphosphonic acids are useful as modifiersas well as flame retardants for synthetic polymeric materials. Thepresent anhydrides of organo-amino-polyphosphonic acids may be used in aquantity which is equal to that of the polymer, but in most instancesfavorable results with respect to improvement in flame-retardance areobtained at concentrations which are definitely lower. In some casesamounts as little as 0.1%, by weight of polymer and anhydride, may beused, although generally it is preferred that amounts of from about 1%to 50% may be used to provide polymeric systems with reduced burningrates.

, Use of the present anhydrides of organo-amino-polyphosphonic acidswith the polymeric materials in quantities which confer beneficialproperties to the polymers with respect to a desired effect, i.e., flameretardance, often confers to the polymer an improvement also in suchcharacteristics as resistance to impact, dimensional stability,moldability, dye receptivity and the like. Hence in order to arrive atoptimum beneficial effect suited to the purposes for which the polymericcomposition is designed, only routine testing, involving variation ofadjuvant quantity is generally required, although in some instances oneor more members of the whole class of the presently provided anhydridesof organo-amino-polyphosphonic acids will be found to impart a degree ofmodifiaction at a low concentration which can be attained by othermembers of the class at significantly higher concentrations.

The flammability test for measuring the burn qualities of polymersamples is for the most part essentially the standard burn test known asASTM-Dl692-D59T or modifications thereof. As used herein a polymericcomposition is considered non-burning if there is no evidence of burning(flame or progressive glow) after removal of the burner and aself-extinguishing sample is one that continues to burn after removal ofthe burner but the flame goes out before the second gauge line isreached.

In general, the anhydrides of organo-amino-polyphosphonic acidanhydrides can be used as a comonomer in place of or in combination ofother conventionally used dibasic or polybasic carboxylic anhydrides,such as phthalic and maleic anhydride, to form synthetic polymericsystems. The anhydrides, for example, can undergo reactions withreactive hydrogen-containing materials which include polyaminescontaining at least two amine groups with a reactive hydrogen on eachgroup and polyhydroxyl-containing organic compounds (containing at leasttwo hydroxyl groups with a reactive hydrogen on each group) includingpolyhydric alcohols, phenols and the like. A distinct advantage of thepresent invention, therefore, is the flexibility which the phosphonicanhydrides exhibit in formulating and preparing polymeric compositions.For example, they can be used with preformed monomers, copolymers andthe like or they can be used as a comonomer to form polymers with otherappropriate monomer materials.

In general, the polyhydric alcohols which are useful in preparingpolymers by reaction with the phosphonic anhydrides include glycerol,pentaerythritol (including diand tripentaerythritol), sorbitol,mannitol, and the glycols (including the alkylene glycols and thepolyalkylene glycols in which the alkylene group is (--CH wherein n isan integer from 2 to such as, ethylene glycol, propylene glycol,butylene glycol, diethylene glycol, dipropylene glycol, triethyleneglycol, tetraethylene gycol, hexamethylene glycol, decamethylene glycoland the like.

In general, the polyamines which are useful in preparing polymers byreaction with the phosphonic anhydrides include the alkylene polyamines(particularly the alkylene diamine, triamine, and tetraamines in whichthe alkylene group is (-CH wherein n is an integer from 2 to 10) suchas, ethylene diamine, diethylene diamine, hexamethylene diamine,decamethylene diamine, triethylene tetraamine, pentamethylene triamine,hexamethylene tetraamine, butylene diamine, and the like.

Usually, all that is necessary is to mix the phosphonic acid andpolyamine and/ or polyhydric organic compounds preferably in amounts ofabout one P--O--P (phosphonic anhydride) group per amine or hydroxylgroup, although amounts on a phosphonic anhydride group to amine orhydroxyl group ratio of from about 1:10 to 10:1 can be used, and heat toelevated temperatures, such as from about 40 C. to the melting point ofthe reactants (under atmospheric pressure, although sub-atmosphericpressures as well as pressures in excess of atmospheric can be used)with temperatures above about 90 C. being preferred. In addition, it issometimes advantageous to employ an inert liquid non-aqueous reactionmedium such as parafiin hydrocarbons, benzene, toluene, Xylene, acetone,dimethyl formamide and the like and after polymerization removing themedium such as by distillation and/or decantation in order to recoverthe polymer.

Synthetic polymeric materials, i.e., those high molecular weight organicmaterials which are not found in nature, with which the presentanhydrides of organo amino-polyphosphonic acids are advantageouslyemployed may be either linear or cross-linked polymers and they may beeither those which are produced by addition polymerization or bycondensation.

An important class of polymers which are beneficially modified accordingto the invention are those obtained from a polymerizable monomercompound having ethylenic unsaturation.

A particularly preferred class of polymers fiame-proofed hereby consistsof the polymerized vinyl and vinylidene compounds, i.e., those havingthe CH =C radical. Compounds having such a radical are, e.g., the solidpolymeric alkenes, such as polyethylene, polypropylene, polyisobutyleneor ethylenepropylene copolymers; polymerized acrylyl and alkacrylylcompounds such as acrylic, chloroacrylic and methacrylic acids,anhydrides, esters, nitriles and amides, for example, acrylonitrile,ethyl or butyl acrylate, methyl or ethyl methacrylate, methoxymethyl or2-(2-butoxyethoxy)ethyl methacrylate, 2-(cyano-ethoxy) ethyl3-(3-cyanopropoxy)propy1acrylate or methacrylate, Z-(diethylamine) ethylor 2-chloroethyl acrylate or methacrylate, acrylic anhydride ormethacrylic anhydride; methacrylamide or chloroacrylamide, ethyl orbutyl chloroacrylate; the olefinic aldehydes such as acrolein,methacrolein and their acetals; the vinyl and vinylidene halides such asvinyl chloride, vinyl fluoride, vinylidene fluoride andl-chloro-l-fluoroethylene; polyvinyl alcohol; the vinyl carboxylatessuch as vinyl acetate, vinyl chloroacetate, vinyl propionate, and vinyl2-ethyl-hexanoate; the N-vinyl imides such as N-vinylphthalimide andN-vinylsuccinimide; the N-vinyllactams such as N-vinylcaprolactams andN-vinylbutyrolactarn; the vinyl aromatic hydrocarbon compounds such asstyrene, a-methylstyrene, 2,4-dichlorostyrene, aor B-vinylnaphthalene,divinylbenzene and vinylfluorene; the vinyl ethers such as ethyl vinylether or isobutyl vinyl ether; vinyl-substituted heterocyclic compoundssuch as vinylpyridine, vinylpyrrolidone, vinylfuran or vinylthiophene;the vinyl or vinylidene ketones such as methyl vinyl ketone or isopenylethyl ketone; vinylidenes cyanide; etc. Homopolymers of the abovecompounds or copolymers or terpolymers thereof are beneficially modifiedby the present phosphonic anhydrides. Examples of such copolymers orterpolymers are those obtained by polymerization of the followingmonomer mixtures: vinyl chlorine-vinyl acetate,acrylonitrilevinylpyridine, styrene-methyl methacrylate; styrene-N-vinylpyrrolidone, cyclohexyl methacrylate-vinyl chloroacetate,acrylonitrile-vinylidene cyanide, methyl methacrylate-vinyl acetate,ethyl acrylate-methacrylamide-ethyl chloroacrylate, vinylchloride-vinylidene chloride-vinyl acetate, etc.

Other presently employed polymers of compounds having the ethylenicgroup, C=C are the homopolymers, copolymers and terpolymers of thea,B-olefinic dicarboxylic acids and the derivatives thereof such as theanhydrides, esters, amides, nitriles and imides, e.g., methyl, butyl,2-ethylhexyl or dodecyl fumarate or maleate, maleic, chloromaleic,citraconic or itaconic anhydride, fumaronitrile, dichlorofumaronitrileor citracononitrile, fumaramide, or maleamide; maleimide orN-phenylmaleimide, etc. Examples of particularly useful copolymers andterpolymers prepared from the 0a,,B-0l6fil1l0 dicarboxy compounds arethe copolymers of maleic anhydride and a vinyl compound such asethylene, propylene, isobutylene, styrene, a-methylstyrene, vinylacetate, vinyl propionate, methyl isopropenyl ketone, isobutyl vinylether, etc., the copolymers of dialkyl fumarate such as ethyl or butylfumarate and a vinyl compound such as styrene, vinyl acetate, vinylidenechloride, ethyl methacrylate, acrylonitrile, etc.

Readily and advantageously modified by the present phosphonic anhydridesare also the polymers and copolymers of unsaturated, cyclic esters ofcarbonic acid, e.g., homopolymeric vinylene carbonate or the copolymersof vinylene carbonate with ethylenic compounds such as ethylene, vinylchloride, vinyl acetate, 1,3-butadiene, acrylonitrile,methacrylonitrile, or the esters of methacrylic or acrylic acid.

Readily and advantageously modified by the present phosphonic anyhdridesare also the polyarylcarbonate polymers such as the linearpolyarylcarbonates formed from diphenols or dihydroxy aromatic compoundsincluding single and fused-ring nuclei with two hydroxy groups as wellas monohydroxy-substituted aromatic residues joined in pairs by variousconnecting linkages. Examples of the foregoing include dihydroxybenzenes, naphthalenes and the like, the dihydroxydiphenyl ethers,sulfones, alkanes [bis(4-hydroxyphenyl)2,2-propane], ketones and thelike.

Advantageously modified by the present phosphonic anhydrides are alsopolymers, copolymers or terpolymers or polymerizable compounds having aplurality of double bonds, e.g., a rubbery, conjugated dienepolymerizate such as homopolymerized 2,3-butadiene, 2-chlorobutadiene orisoprene and linear copolymers or terpolymers such asbutadiene-acrylonitrile copolymer, isobutylene-butadiene copolymer(butyl rubber) butadiene-styrene copolymer of2-chl0ro-butadiene-vinylidene cyanide -acrylonitrile terpolymer; estersof saturated dior polyhydroxy compounds with olefinic carboxylic acidssuch as ethylene glycol dimethacrylate, triethylene glycol dicrotonateor glyceryl triacrylate; esters of olefinic alcohols with dicarboxylicacids or with olefinic monocraboxylic acids such as diallyl adipate,divinyl succinate, diallyl fumarate, allyl methacrylate or crotylacrylate and other diethylenically unsaturated compounds such as diallylcarbonate, divinyl ether or divinylbenzene, as well as the cross-linkedpolymeric materials such as methyl methacrylate-diallyl methacrylatecopolymer or butadiene-styrene-divinyl-benzene terpolymer.

Polymerized materials prepared by subsequent reaction of the preformedvinyl polymers, e.g., polyvinyl alcohol, the polyvinyl acetals such aspolyvinyl formal or polyvinyl butyral, or completely or partiallyhydrolyzed polyacrylonitrile are likewise modified in properties by thepresent phosphonic anhydrides to give polymeric materials of enhancedutility.

Polymeric materials with which the present phosphonic anhydrides can beemployed as adjuvants are also polymers which contain elements such assulfur, phosphorus, boron or silicon, e.g., the sulfides, sulfones,sulfoxides, sulfites, sulfates and sulfonates such as the polymers andcopolymers of vinyl sulfide, vinyl sulfone, Z-propenyl sulfoxide,ethylene, sulfonic acid and its salts, esters and amides, and sulfonatedpolystyrene; the olefin-sulfur dioxide polymers, the phosphines,phosphites, phosphates and phosphonates such as diphenylvinylphosphine,allyl phosphite and methallyl phosphite, ethylene phosphonic acid andstyrenephosphonic acids and their salts, esters and amides; the silanessuch as dimethylvinylsilane, diphenylvinylsilane andmethylphenylvinylsilane, etc.

A class of synthetic polymeric materials with which the presentphosphonic anhydrides are very useful comprises the cellulosederivatives, e.g., the cellulose esters such as cellulose acetate,cellulose triacetate, or cellulose acetate butyrate, the celluloseethers such as methyl or ethyl cellulose, cellulose nitrate,carboxymethyl cellulose, cellophane, rayon, regenerated rayon, etc. Thephosphonic anhydrides may be incorporated into films of such cellulosederivatives by adding them to the solutions from which the films arecast or into the melts from which the fibers are extruded.

The present phosphonic anhydrides are particularly suited to themodification of liquid resin compositions of the polyester type, e.g.,the linear polyesters which are obtained by the reaction of one or morepolyhydric alcohols with one or more il-unsaturated polycarboxylic acidsalone or in combination with one or more saturated polycarboxylic acidcompounds, or the cross-linked polyester resins which are obtained byreacting the linear polyester with a compound containing a CH =C group.

The crosslinking component of the presently modified polyester resin maybe, e.g., styrene, the nuclear or sidechained substituted styrenes suchas 3,4-dichlorostyrene, a-chloro-styrene, u-methylstyrene; othervinyl-substituted hydrocarbons such as ozor fl-vinylnaphthalene or4-vinylbiphenyl; the olefinic carboxylic acids and the esters, nitriles,amides and anhydrides thereof such as acrylic acid, methacrylic acid,ethyl acrylate, or acrylonitrile; the vinyl esters such as vinyl acetateor vinyl chloroacetate; the olefinic ketones such as ethyl vinyl ketoneand isopropenyl methyl ketones; the alkanes such as isobutylene and 2-pentene; the olefinic ethers such as vinyl ethyl ether and vinyl,isobutyl ether; etc.

The epoxy resins are another class of polymeric materials with which thepresent phosphonic anhydrides are compatible and are advantageouslyused. These resins are condensation products formed by the reaction of apolyhydroxy compound and epichlorohydrin, which condensation productsare subsequently cured by addition of cross-linking agents. The hydroxycompound may be e.g., ethylene glycol, 4,4 isopropylidenediphenol, etc.The cross-linking agent employed in the curing or hardening step may bea dicarboxylic compound such as phthalic anhydride or adipic acid, butis more generally a polyamine such as ethylene diamine, mor p-phenylenediamine or diethylenetriamine.

The polyurethanes comprise another class of polymeric materials whichare beneficially modified by the present phosphonic anhydrides. Thepolyurethanes, like the abovementioned polyesters, are commercialmaterials which are employed in structural applications, e.g., asinsulating foams, in the manufacture of textile fibers, as resin basesin the manufacture of curable coating compositions and as impregnatingadhesives in the fabrication of laminates of woods and other fibrousmaterials. Essentially the polyurethanes are condensation products of adiisocyanate and a compound having a molecular weight of at least 500and preferably about 1500-5000, and at least two reactive hydrogenatoms, i.e., hydrogen atoms determinable by the Zerewitinotf method. Theuseful active-hydrogen containing compounds may be polyesters preparedfrom poly carboxylic acids and polyhydric alcohols, polyhydricpolyalkylene ethers having at least 2 hydroxy groups, polythioetherglycols, polyesteramides, etc.

The polyesters or polyesteramides used for the production of thepolyurethane may be branched and/or linear, e.g., the esters of adipic,sebacic, G-aminocaproic, phthalic, isophthalic, terephthalic, oxalic,malonic, suecinic, maleic, cyclohexane-1,2,-dicarboxylic, cyclohexane-1,4dicarboxylic, polyacrylic, naphthalene-1,2-dicarboxylic, fumaric,itaconic, etc., with polyalcohols such as ethylene glycol, diethyleneglycol, pentaglycol, glycerol, sorbitol, triethanolamine,di-(fl-hydroxyethyDether, etc. and/or amino-alcohols such asethanolamine, 3-amin0- propanol, 4-aminopropanol,5-aminopentanol-L6-aminohexanol, IO-aminodecanol,6-amino-5-methylhexanol-1, p-hydroxymethylbenzylamine, etc.; and withmixtures of the above polyalcohols and amines, ethylene diamine,hexamethylene diamine, 3-methylhexamethylene diamine, decamethylenediamine and m-phenylenediamine, etc. and/or amino-alcohols, etc. In theesterification, the acid per se may be used for condensation or, wheredesirable, equivalent components such as the acid halide or anhydridemay be used.

The alkylene glycols and polyoxyalkylene or polythioalkylene glycolsused for the production of the polyurethanes may comprise ethyleneglycol, propylene glycol, butylene glycol-2,3, butyleneglycol-1,3,2-methylpentanediol 2,4,2 ethylhexanediol 1,3, hexamethyleneglycol, styrene glycol and decamethylene glycol, etc., and diethyleneglycol, triethylene glycol, tetraethylene glycol, polythioethyleneglycol, polyethylene gycols 200, 400 and 600 etc., dipropylene glycol,tripropylene glycol, trithiopropylene glycol, polypropylene glycols 400,750, 1,200 and 2,000 etc.

Broadly, any of the polyesters, polyisocyanate-modified polyesters,polyesteramides, polyisocyanate modified polyesteramides, alkyleneglycols, polyisocyanate-moditied alkylene glycols, polyoxyalkyleneglycols and polyisocyanate-modified polyoxyalkylene glycols, etc. havingfree reactive hydrogen atoms, free reactive carboxylic and/or especiallyhydroxyl groups may be employed for the production of the polyurethanes.Moreover, any organic compound containing at least two radicals selectedfrom the class consisting of hydroxyl and carboxyl groups may beemployed.

The organic polyisocyanates useful for the production of thepolyurethanes include ethylene diisocyanate, ethylidene diisocyanate,propylene-1,Z-diisocyanate, butylene 1,3 diisocyanate,hexylene-1,6-diisocyanate, cyclohexylene-1,2-diisocyanate, m-phenylenediisocyanate, 2,4- toluylene diisocyanate, 2,6-toluylene diisocyanate,3,3- dimethyl-4,4'-biphenylene diisocyanate, 3,3-dimethoxy-4,4'-biphenylene diisocyanate, 3,3'-diphenyl-4,4-biphenylenediisocyanate, 4,4'-biphenylene diisocyanate, 3,3-dichloro 4,4biphenylene diisocyanate, triphenylmethane triisocyanate,1,5-naphthalene diisocyanate or polyisocyanates in a blocked or inactiveform such as the bisphenyl carbamates of toluylene diisocyanate,p,p'-diphenylmethane diisocyanate, p-phenylene diisocyanate and1,5-naphthalene diisocyanate, etc.

For preparation of the flame-retardant polyurethanes, the presentphosphonic anhydrides are preferably added to a mixture of the reactantsand catalyst before' hardening. The hardened molded pieces or foams arerendered flame-retardant by the inclusion therein of the phosphonicanhydride in quantities of from about 2% to 25% by weight of thepolyurethane. Use of the present phosphonic anhydrides in thepolyurethane foams can also, in some applications, improve themechanical properties of the foams.

Phenolic resins are also beneficially modified by the present phosphonicanhydrides, which compounds can be incorporated into the resin either bymilling in molding applications or by addition to film-forming orimpregnating and bonding solutions previous to casting. Phenolic resinswith which the present compounds are employed are, for example, thephenolaldehyde resins prepared from phenols such as phenol, cresol,xylenol, resorcinol, 4-butylphenol, 4-phenylphenol, and aldehydes suchas formaldehyde, acetaldehyde, or butyraldehyde in the presence ofeither acidic or basic catalysts, depending upon whether the resin isintended for use as a molding or extruding resin or as the resin base incoating and impregnating compositions.

The aminoplasts comprise another group of aldehyde resins which arebeneficially modified by the present phosphonic anhydrides. Examplesthereof are the heat-convertible condensation products of an aldehydewith urea, thiourea, guanidine, cyanamide, dicyandiamide, alkyl or arylguanamines, and the triazines such as melamine,2-chloro4,6-diamino-l,3,5-triazine and 2-hydroxy-4,6-diamino 1,3,5triazines. The present adjuvants are compatible with the aminoplasts;and depending upon the quantity of phosphonic anhydride used, they serveto modify their physical properties as well as to render themfire-retardant. When the aminoplasts are destined for use asimpregnating agents, bonding adhesives, coatings and casting of films,the phosphonic anhydrides are incorporated into solutions or suspensionsin which the aminoplast is carried. The resulting mixtures give strong,fireretardant laminates when sheets of paper, glass, cloth or fabric areimpregnated therewith and cured.

Also beneficially modified by the present phosphonic anhydrides are thenylons, i.e., the superpolyamides which are generally obtained by thecondensation of a diamine, e.g., hexamethylenediamine with adicarboxylic acid, e.g., adipic acid. Depending upon the quantity ofphosphonic anhydride employed and the individual nature of the compound,there are obtained flame-retardant and/or dye receptor elfects.

Other polyamides with which the present phosphonic anhydrides arebeneficially employed, e.g., for improvement in reducing burning rates,are the polypeptides which may be prepared, e.g., by reaction ofN-carbobenzyl oxy- =glycin with glycine or a mixture of glycine andlysine, or an N-carboxy amino acid anhydride such as N-carboxy-DL-phenyl-alanine anhydride; the polymeric lactams, e.g.,polycaprolactam, piperidone, 2-oxohexamethyleneimine and other cyclicamides. The present phosphonic anhydrides can be incorporated intomolding or extruding compositions for flame-retardant effect and/or tomodify the physical properties of such compositions.

The present phosphonic anhydrides are also advantageously employed asadjuvants for polymeric aldehydes, fig, homopolymeric, high-molecularweight formaldeyde.

The present phosphonic anhydrides are also adjuvants for linear polymersobtained by the self-condensation of bifunctional compounds generally,e.g., the polyethers which are derived by the self-condensation ofdihydric alcohols such as ethylene glycol, propylene glycol orhexamethylene glycol; the polyesters which are obtained by theself-condensation of hydroxy acids such as lactic acid or4-hydroxybutyric acid, the polyamides which are prepared by theself-condensation of amino carboxylic acids such as 4-aminobutyric acidor G-aminocaproic acid; the polyanhydrides which are formed by theselfcondensation of dicarboxylic acids such as sebacic acid or adipicacid, etc. The present phosphonic anhydrides are flame-retardants forsuch self-condensation products, generally; and where transparentizingeffect and dye receptivity are lacking, the phosphonic anhydrides areoften instrumental in ameliorating such deficiencies.

The following examples are presented to illustrate the invention, withparts and percentages by weight being used in the examples unlessotherwise indicated. All polymeric compositions illustrated in thefollowing examples will exhibit reduced burning rates and can beclassified as either non-burning or self-extinguishing.

Example I A copolymeric composition is obtained by heating about 0.15mols of ethylene diamine and about 0.5 mol of aminotri(methylenephosphonic anhydride) in benzene to about C. for about 4hours. The reaction batch is cooled to room temperature and the benzenedistilled oif yielding a polymeric composition which softens at about250280 C.

Example 11 A copolymeric composition is also obtained by blending about0.3 mol of hexamethylene diamine and about 0.1 mol of an indicatedphosphonic anhydride compound, and heating the mixture for 3 hours atabout 150 C. and thereafter cooling to room temperature. The addedphosphonic anhydride compounds are:

(1) amino tri(methylenephosphonic anhydride) (2) anhydride of dodecylamino di(methylenephosphonic acid) (3) anhydride of tetradecyl aminodi(methylenephosphonic acid) (4) anhydride of ethylene diaminetetra(methy1enephosphonic acid) (5) anhydride of hexamethylene diaminetetra(methylenephosphonic acid).

Example III A copolymeric composition is also obtained by blending about0.3 mol of ethylene glycol and about 0.1 mol of an indicated phosphonicanhydride compound and then heating the mixture at C. for about 1 hour.Upon cooling to room temperature the composition sets to a solidpolymeric composition. The added phosphonic anhydride compounds are:

(1) amino tri(methylenephosphonic anhydride) (2) anhydride of dodecylamino di(methylenephosphonic acid) (3) anhydride of tetradecyl aminodi(methylenephosphonic acid) (4) anhydride of ethylene diaminetetra(methylenephosphonic acid) (5) anhydride of hexamethylene diaminetetra(methylenephosphonic acid).

Example IV A copolymeric composition is obtained by dissolving about 4.7parts of amino tri(methylenephosphonic anhydride) in about parts ofdimethyl formamide at a 11 reflux temperature of about 125 C., andadding about 3.5 parts of hexamethylene diamine to the solution underrefluxing. The polymeric composition precipitates from the solution inthe form of a solid material and after cooling to room temperature isremoved from the dimethyl formamide solution.

Example V A polymeric composition is obtained by blending 41 parts ofoleic acid, 21 parts of glycerine, 17 parts of an indicated phosphonicanhydride compound, and a trace of toluene sulfonic acid and heating themixture to about 140 C. under a flowing nitrogen blanket sufiicient toexclude air and to remove by-product water. After about 30 minutesgelatin occurs and the batch is cooled to room temperature to yield asolid polymeric composition. The added phosphonic anhydride compoundsare:

(1) amino tri(methylenephosphonic anhydride) (2) anhydride of dodecylamino di(rnethylenephosphonic acid) (3) anhydride of hexamethylenediamine tetra(methylenephosphonic acid).

Example VI This example illustrates the preparation of a rigidpolyurethane foam using one of the indicated phosphonicanhydridestherein as the flame-retardant.

Ingredient Parts Methyl glucoside based polyol 100.0Trichloromonofiuoromethane 35.0 Silicone Y-4316 1 2.0 Tetramethylbutanediamine 1.5 Phosphonic anhydride 2 10.0

Polyisocyanate Mondur MR 108.0

1 Silicone Y-4316 is a trademark name for a silicon foam stabilizer soldby Union Carbide.

2 Phosphonic anhydride (1) amino tri(methylenephosphonic anhydride) (2)anhydride of tetra decyl amino di(methylenephsphonic acid) (3) anhydrideof hexamethylene 'diamine tetra(methy1- enephosphonlc acid).

3 Polylsocyanate Mondnr MRa polymethylene polyphenylisoeyanate having anavailable NCO content of about 32% and a viscosity at 25 C. of 200:50cps.

For the above formulation, all of the components except thepolyisocyanate are blended to a homogeneous mixture, and then thepolyisocyanate is added, the mixture blended thoroughly, and then isallowed to polymerize and rise.

Example VII A composition is also obtained by adding one of theindicated phosphonic anhydride compounds in an amount sufiicient to beabout by weight based on the weight of the total solids content of a 10%benzene solution of a 72:28 molar ratio styrene-acrylonitrile copolymer.The benzene is distilled off yielding a polymeric composition. The addedphosphonic anhydride compounds are:

( 1) amino tri(methylenephosphonic anhydride) (2) anhydride of phenylamino di(methylenephosphonic acid) (3) anhydride of cyclohexyl aminodi(methylenephosphonic acid).

Example VIII To a polymer blend of an unsaturated polyester prepared bycondensing one mol of an indicated phosphonic anhydride, /2 mol ofmaleic anhydride, /2 mol of phthalic anhydride and 2.1 mols of propyleneglycol to an acid number of about 40 to 200 C., cooling the mixture anddissolving the mixture in a sufficient amount of styrene monomer so thatthe resulting mixture comprises 30 parts styrene monomer to 70 parts ofpolyester. There is added a small amount (3% w./w.) of benzoyl peroxideand the resulting mixture is polymerized at 80 C. yielding athermosetting resin. The added phosphonic anhydride compounds are:

12 (1) amino tri(methylenephosphonic anhydride) (2) anhydride ofdodecylphenyl amino di(methylenephosphonic acid) (3) anhydride oftrimethylene diamine tetra(methylenephosphonic acid).

Example IX To a granular blend of a polystyrene and butadienestyrenecopolymer containing about 6% by weight of the copolymer there is addedone of the indicated phosphonic anhydride compounds in an amout of about4% by weight by blending for 15 minutes in a tumbling type laboratoryblender and then extruding the blend into rods. The added phosphonicanhydride compounds are:

( 1) amino tri(methylenephosphonic anhydride) (2) anhydride of methylamino di(methylenephosphonic acid).

Example X To melted samples of a natural high molecular weight lowdensity polyethylene having a density of about 0.9, a melt index ofabout 0.3 gm./ 10 min., a softening temperature of about 105 C., and atensile strength (ultimate) of 2300 p.s.i.g., various amounts of one ofthe indicated phosphonic anhydrides suflicient to make compositionswherein the added anhydride comprises from about 4 to 8% of the totalweight of the composition are added. The samples are cooled to roomtemperature to provide polymer compositions. The added phosphonicanhydride compounds are;

(1) amino tri(methylenephosphonic anhydride) (2) anhydride of hexylaminodi(methylenephosphonic acid) (3) anhydride of ethylene triaminepenta(methylenephosphonic acid).

Example XI To a 5% solution of a polyvinyl formal in ethylene dichloridethere is added one of the indicated phosphonic anhydride compounds in aquantity which is about 20% by weight of the total solids content of thesolution. Films are cast from such solutions and then air dried forabout 24 hours. The added phosphonic compounds are:

(1) amino tri(methylenephosphonic anhydride) (2) anhydride oftriethylene tetraamine hexa(methylenephosphonic acid).

Example XII Improved films are also obtained when one of the indicatedphosphonic anhydride compounds is added to a 10% solution of a 50:50molar ratio styrene-methyl methacrylate copolymer in benzene in anamount sufficient to be about 30% by weight of the total solids contentand then cast into films which are flexible. The added phosponicanhydride compounds are:

(1) amino tri(methylenephosphonic anhydride) (2) anhydride of butylamino di(methylenephosphonic acid).

Example XIII With about 3 parts of a commercially available condensationproduct of linoleic acid and a polyamine having an amine value of from290-320 and a viscosity of 120 poises at 40 C., there is mixed 7 partsof diglycidyl ether of Bisphenol A and a sufiicient amount of one of theindicated phosphonic anhydrides to make a composition having about 16%by weight, based on the weight of the total composition, of thephosphonic anhydride. The resulting reaction mixture is poured into asmall aluminum pan (coated with a silicon grease to prevent sticking)and heated in an oven at C. for about 2 hours. After cooling to roomtemperature an epoxy resinous product is obtained. The added phosphonicanhydride compounds are:

(1) amino tri(methylenephosphonic anhydride) 13 (2) anhydride of dodecylamino di(methylenephosphonic acid) (3) anhydride of aminotri(ethylidenephosphonic acid).

Example XIV To samples of a commercial cellulose acetate butyrate havingan average acyl content of 13% and 37% butyryl and a viscosity range of17-33 seconds (64-124 poises) as determined by ASTM method D-1343-54T inthe solution described as Formula A, ASTM method D-871 54T are blendedon hot mill rolls a suflicient amount of one of the indicated phosphonicanhydrides such that the final compositions contain from about to 15% byweight of the added phosphonic anhydrides. After blending the samplesare cooled to room temperature to obtain a polymeric composition. Theadded phosphonic anhydrides are:

(1) amino tri(methylenephosphonic anhydride) (2) anhydride of hexydecylamino di(methylenephosonic acid) (3) anhydride of phenylethyl aminodi(methylenephosphonic acid).

Example XV To a 10% ethylene dichloride solution of polyvinyl acetatethere is added one of the indicated phosphonic anhydride compounds in aquantity which is /2 by weight to that of the polyvinyl acetate presentin the solution. Films cast from the resulting mixture are flexible. Theadded phosphonic anhydride compounds are:

(1) amino tri(methylenephosphonic anhydride) (2) anhydride of octylamino di(methylenephosphonic acid) (3) anhydride of ethylene diaminetetra(methylenephosphonic acid).

Example XVI To melted samples of a commercial rigid polymethylmethacrylate polymer there is blended on hot mill rolls one of theindicated phosphonic anhydrides in an amount suflicient to provide aboutof the anhydride per total weight of the composition. The samples aremilled into sheets in order to obtain polymeric compositions. The addedphosphonic anhydrides are:

(1) amino tri(methylenephosphonic anhydride) (2) anhydride of oleylamino di(methylenephosphonic acid) (3) anhydride of hexamethylenediamine tetra(methylenephosphonic acid).

Example XVII To 100 parts of a polyvinyl chloride resin there is added50 parts of dioctyl phthalate and 50 parts of aminotri(methylenephosphonic anhydride). The mixture is placed on hot millrolls and blended. When thoroughly blended, the product is stripped fromthe rolls and pressed into square shaped pieces which are soft pliableplastic.

Example XVIII A salt is prepared from hexamethylene diamine and adipicacid by mixing about 144 parts of amine with about 150 parts of the acidin the presence of 1300 parts of 95% ethyl alcohol and 210 parts ofwater. The mass is warmed until complete solution occurs and then cooledto obtain crystals of hexamethylene diammonium adipate. To this salt isadded about 16 parts of amino tri(methylene phosphonic anhydride) andthe mixture heated for about three hours with an equal weight of mixedxylenols (B.P. 2l8-222 C.) and the entire reaction mass is then pouredgradually with stirring into a large volume of ethyl alcohol. Themodified polyamide precipitates as a granular powder and is filtered,washed with alcohol and dried.

What is claimed is:

1. A polymer comprising a reactive hydrogen-containing material selectedfrom the group consisting of polyhydric compounds and polyaminecompounds, copolymerized with an anhydride of an organo-amino-polyphosphonic acid having the formula:

wherein n is an integer 0 to l, X and Y are selected from the groupconsisting of hydrogen and alkyl groups containing from 1 to 6 carbonatoms, and R is selected from the group consisting of hydrogen,aliphatic, aryl, alkaryl,

aralkyl, alicyclic, and

x (AM. I 1',

m is an integer from 1 to 10, R and R are each selected from the groupconsisting of hydrogen, alkyl groups containing from 1 to 6 carbonatoms,

and R does not contain over 6 nitrogen atoms; said anhydridecharacterized by exhibiting an infra-red absorption spectrumcharacteristic of a phosphonic anhydride and an increase in the meltingpoint over the corresponding organo-amino-polyphosphonic acid.

2. A process for preparing a polymer of claim 1 which comprises reactingsaid reactive hydrogen-containing material with said anhydride attemperatures above about 40 C. in an amount on a phosphonic anhydridegroup to a reactive hydrogen ratio of from about 1:10 to 10:1.

3. A process according to claim 2, wherein said amount is about onephosphonic anhydride group per reactive hydrogen.

4. A polymer according to claim 1, wherein said anhydride is ananhydride of an amino tri(lower alkylidenephosponic acid) having theformula:

wherein X and Y are selected from the group consisting of hydrogen andalkyl groups containing from 1 to 6 carbon atoms.

5. A polymer according to claim 4, wherein said polymer is a copolymerof a polyhydric compound and an hydride having the formula N(CH P O 6. Apolymer according to claim 4, wherein said polymer is a copolymer of apolyamine and an anhydride having the formula N(CH P O 7. A polymeraccording to claim 1, wherein said anhydride is an anhydride of an alkylamino di(lower alkylidenephosponic acid) having the formula:

Mai Y OH:

wherein X and Y are selected from the group consisting of hydrogen andalkyl groups containing from 1 to 6 carbon atoms and R is an alkyl groupcontaining from 1 to 20 carbon atoms.

8. A polymer according to claim 7, wherein said anhydride is ananhydride of dodecyl amino di(methylenephosphonic acid).

9. A polymer according to claim 7, wherein said anhydride is ananhydride of tetradecyl amino di(methylenephosphonic acid).

15 10. A polymer according to claim 1, wherein said anhydride is ananhydride of an alkylene diamine tetra- (methylenephosphonic acid)having the formula:

wherein n is an integer from 1 to 10 inclusive.

11. A polymer according to claim 10, wherein said anhydride is ananhydride of ethylene diamine tetra(methylenephosphonic acid).

12. A polymer according to claim 10, wherein said anhydride is ananhydride of hexamethylene diamine tetra- -(methylenephosphonie acid).

16 References Cited UNITED STATES PATENTS 2,841,611 7/ 1958 Bersworth260502.5 2,891,915 6/1959 McCormack et al. 2602 2,963,451 12/ 1960Coates 2602 3,298,968 1/ 1967 Fierce 2602 SAMUEL H. BLECH, PrimaryExaminer US. Cl. X.R.

